# Tag Info

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Blast can definitely kill you, although it is only lethal at much shorter ranges compared to shrapnel. A building can be destroyed by 5psi overpressure while a Human can withstand up to 45psi and live. Some data here: A 5 psi blast overpressure will rupture eardrums in about 1% of subjects, and a 45 psi overpressure will cause eardrum rupture in ...

5

This is a fun question and has about 4 or 5 different factors at play: Types of forces involved: Pressure vs. Inertia Types of resistance involved: Rigidity vs. Plasticity Objects involved: Soldiers vs. Buildings Scenario: Damage from a bomb blast (energy wave) vs. shrapnel impact/penetration (kinetic collision). How damage is applied with: Blast - the ...

4

The underlying principle is to use interferometry and the Doppler effect to remotely measure the velocity of a reflecting surface. When a moving object is illuminated with coherent light it reflects it with a wavelength shift proportional to its velocity. This is the well-known Doppler effect. The frequency shift relates to the source's velocity as ...

3

Is it possible to measure the temperature of something using sound...? Yes, it is not only possible, it is available commercially. It is especially useful in harsh environments where conventional temperature probes might not survive. For example, TMT makes an acoustic system for measuring 2-D temperature distributions in blast furnaces: The ...

3

The blast overpressure of the explosion is a very strong shock wave which can kill humans. There are a number of ways an explosion without shrapnel can do harm to people: Rupturing of the hollow organs due to rapid compression and expansion by the shock wave. The body can get thrown through the air if a strong detonation occurs nearby. Impact of the body ...

3

First, check your algebra. You actually end up with units $\sqrt{\frac{m\cdot Pa}{kg}}$. Now, one Pascal is one Netwon per meter squared, $Pa=\frac{N}{m^2}$. One Newton is one kilogram-meter per second squared, $N=\frac{kg\cdot m}{s^2}$. Thus one Pascal is $Pa=\frac{kg}{m \cdot s^2}$, and if we plug that into $\sqrt{\frac{m \cdot Pa}{kg}}$ we get units of ...

2

Ok, reading up about it, here's what I think is happening. Just a guess. I think when an anvil rings, there are parts of the anvil that vibrate vigorously, and parts that are self-damping. Or perhaps there's a surface standing wave, some areas with nodes and some areas with antinodes. In any case, the vibrations happen in specific areas of the anvil. By ...

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Blacksmith Forum This answer is just to illustrate how one blacksmith reduced the noise level without resorting to magnets or weights. Over time, and literally being hammered every day, even a well tied down anvil must loosen it's bolts and restraining materials and start to vibrate and produce the noise mentioned. The more mass involved, the less ...

2

Researchers at the Ohio State University have shown that heat can be controlled with a magnetic field, and that it should also be possible to affect sound waves with a magnetic field. Apparently phonons, the quasi-particles associated with compressional waves and vibrations in a lattice, have magnetic properties. Here is an account of the study: ...

2

Run this to determine which frequency range(s) you can hear http://onlinetonegenerator.com/hearingtest.html If you can hear 14kHz-15kHz then the problem is with the radio or transmitter otherwise it is your hearing I imagine that loss of hearing at an intermediate frequency would be rare especially if it is in both ears. My bet would be with poor speaker ...

2

It depends what you mean by "function optimally". If you want it to be loud, it must transfer energy to the air and thus it's vibrational energy must decay rapidly. Imagine that the tines are large thin vanes (close together) so they transfer most of their energy to the air in a few vibrations. You will not hear or measure a precise frequency. If "function ...

1

First of all, the effect is totally real. Here is an example YouTube video how it sounds (and a recipe how to fix it): https://www.youtube.com/watch?v=x5ruAZ4Useg I am actually getting much more melodic sounds from the speakers! ;-) And I have heard the same melodic reactions of PC speakers in many people's scientific talks and even in TV programs. ...

1

If I understand your question correctly, the answer is "yes". For most energy conversion processes, the "inverse" process exists. Typically though, as you go from one to the other, and back again, you will lose some efficiency - think of it as the universe entropy increasing at every step of the way. Specifically, with regard to your two examples: The ...

1

Yes. The simplest change one could make to change the range is to modify the end condition. A pipe based instrument with an air reed has an open end at the air reed. The other end could be either open or closed. If that end is closed, the range goes down an octave, and the overtones change (so the tone, or timbre, changes, too). Also, changing from a ...

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The other answers already mention pressure and heat. A bomb sets nearby bodies in motion with a speed depending on the strength of the explosion, the distance to the body, and how much surface area of the body was facing the bomb. While - as explained in the other answers - being set in motion is rarely lethal, being smashed against a wall can easily lead ...

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